APC 600XL, 900XL, 2000XL user manual Option switches, Replace battery, Overload

5.0 Operation

5.5.3 Replace battery

In the event the UPS's battery fails a battery test, the UPS will emit "chirps" for a period of 1 minute. If the UPS is left operating while in this condition, the UPS will emits chirps once every 5 hours until a successful battery test is completed.

5.5.4 Overload

The UPS will emit a loud, sustained tone when overloaded. When an overload is applied while on-line, the alarm will sound until the overload is removed. If the overload is applied while on-battery, the alarm will sound until the UPS Enable control is switched off.

5.6 Option switches

Note: Option switches may be thrown at any time and take effect immediately.

5.6.1 Option switch 1

The UPS contains utility fault detection circuitry that is extremely sensitive to line voltage distortions including spikes, notches, sudden dips and swells. The UPS is factory set to react to such line voltage distortions by transferring the load immediately to on- battery operation. This affords maximum protection for all load types. Where power quality is poor due to local cyclic heavy load switching or use of inexpensive fuel generators, the UPS may be caused to transfer to on-battery operation very often. If the UPS is powering loads that are known to operate normally under such conditions, such behavior is undesirable as battery capacity is being spent unnecessarily.

The user may set Option switch 1 to the on ( I ) position in order to desensitize the UPS to rapid low amplitude line voltage fluctuations. When this is done, the UPS's upper transfer voltage is also increased by 3%, for a total of 13% above the nominal input voltage. This allows the UPS's battery charger to maintain maximum possible battery capacity, saving it for gross utility failures.

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